Automatic signal.



- 15ATENTEDDEG.5,1905. A. B. BURT & P. T. V'AN A.

. AUT TIG SIGNA APPLIGA FILED JUNE 5. 1905.

ANDREWR; RURTAND- FRANK ,T. VANAITA, or SAN RR NoIsoo.

CALIFORNIA.

AUTOMATIC SIGNAL.

' j To-all whom it may concern: 1

Be it known. that we, ANDREW B. BURT an FRANK T. VANATTA, citizens of the United States,;residing at San Francisco, county of San. Francisco, and State of. California, have inventedcertainnew and usefullmprovements in AutomaticSignals, of which thefollowing is a: specification.

Our invention relates to automatic signals. One object of theinvention is the-provision of novel means which will. automatically indicate at anygiven point the exact part of the road the train. is on at the time the. signal is operated.

Another object of the invention is the provision of means for automatically indicating the direction in which the train; is traveling.

Heretofore signals of this character exposed the signal to view, but did not indicate thedirection in which1the'train was traveling, and when they did so indicate the signal was operated by separate mechanism. Our invention is designed to obviate this difliculty and to provide means which will not only indicate the location of the train, but will at the same time indicate the direction of travel.

The invention consistsin the novel arrangement and combination of parts, which will be fully described hereinafter and the novel features pointed out in the appended claims.

In the accompanying drawings, Figure 1 is a side elevation. Fig. 2 is a section at a: w,

I Fig. 1, and showing in dotted lines the position of the tube when compressed by the car- Wheel. Fig. 3 is a section at y y of Fig. 1, and Fig. a detail section of a modified form of compressible tube.

Referring more especially to the drawings,

1 represents the ordinary rail, which is supported on cross-ties 2 of sulficient height at the point where the signal mechanism is lodated to give plenty of room. Rigidly secured to the rail, preferably over one or more cross-ties 2, is achair 3, which has its top flush with the tread of the rail and is provided adjacent the tread with a depressed portion 4, the purpose of which will be hereinafter described. Suitably secured to the rail at either end of the chair 3 are cylinders 5 of any suitable type, which are provided with pistons 6 and piston-rods 7. Connected to each of these cylinders and communicating therewith is a heavy compressible tube 8, which lies inter- Specification of Letters Patent. Application filed June 5,1905. Serial n. 263,782..

.Patented Dec. 5, 1905.

mediate the cylinders in the depressed portion 4:. off the chair 3-and projects half of its diameter or substantially double the thickthe tread of the rail, so that when the tube is compressed to, its full extent it will have the aperture through it closed. I Depending from the piston-rods 7 are arms 9,,which are provided with contact members 10, adapted to engage thecontact-points 11 of two-normallyopen circuits and to close; the saidcircuits, according to the direction of travel of the train.

The operation of the device is as follows:

Wewill suppose, for instance, that the train istraveling in the direction indicated by the arrow at; in Fig.1.. The wheel B will engage and compress the tube, starting from the point marked 0, and will, as it travels forward, force the air held in the tube into the cylinder at the right. cylinder forward, compressing the air ahead and forming a partial Vacuum in the cylinder on the left, so that when the wheel releases the tube, (but not until after the contact member has closed the circuit at the end,) the suction in the cylinder on the left caused by the vacuum and the pressure ahead of the piston on the right tends to restore the .parts to their normal position. It will be obvious that should the train be traveling in the opposite direction the device would operate in the same manner, but would operate an entirely diflerent signal.

To those versed in the art the uses to which this device will be and. can be put are innumerable, and it will be evident that the .piston of the cylinders could be made to opcrate any class of signal other than an electric one. The tube might be sunk in a depression made in the rail itself, or otherwise, and we do not care to limit ourselves to the exact construction shown, which is used for illustration only, but desire to cover broadly the .many modifications which could be resorted to without departing from thespirit of the invention.

As shown at8 in Fig. 4:, the compressible tube may be made square or rectangular in cross-section with its opening normally of elliptical form, and we may prefer to use this form of tube in many instances.

Having thus described our invention, what ness. of the'wall of the tube above the level of This moves the piston in that we claim as new, and desire to secure by Letters Patent, ik

1. Asignalingdevice,comprising pneumatic means engageable directly by a moving body to operate independent signals to indicate the direction of travel of said body, and means for supporting said pneumatic means in engageable position.

2. In combination with a roadway, a tube held in juxtaposition thereto and engageable bya moving body approaching from either direction, independent pressure-operable de vices connected to the respective ends of said tube, and independent signaling devices operable by the respective pressure devices aforesaid.

3. In a device of the class described, the combination with a rail, of a chair adjacent thereto, a pneumatic tube held on said chair adjacent the rail and adapted to be engaged by a moving body from either direction, and circuit-closing devices operated when the air is compressed in said tube by said moving body.

4. In a device of the class described, the combination with a rail, of a chair adjacent thereto, a pneumatic tube held on said chair adjacent the rail, and adapted to be engaged by a moving body from either direction, cylin-' ders connected to said tube, pistons in said cylinders, and circuit-closing devices operated by said pistons when the air from said tube operates said pistons.

5. In a device of the class described, the combination with a rail, of a chair adjacent thereto, a pneumatic tube seated on the chair and projecting above the tread of the rail, said tube adapted to be compressed from either direction by a moving body, cylinders connected to the respective ends of the tube, pistons in said cylinders adapted to be operated when the air is compressed in said tube by engagement with the moving body, a plurality of electrical-circuit contacts, and a contact member carried by each of said pistons adapted to close one of the circuits when the pistons are operated according to the direction of travel of the moving body.

In testimony whereof we hereunto afiix our signatures in presence of two witnesses.

ANDREW B. BURT. F. T. VANATTA.

Witnesses:

J. M. ELLIS, JAs. BURT. 

